1. Field of the Invention
The invention relates to an outdoor flame heater, and more particularly to the radiant heat lifting device having a heat-resistant net tube mounted on a top of a glass tube for accumulating the heat of a flame and producing infrared to increase the radiation thermal of the heater and thus enhance the effect of the outdoor heating.
2. Description of the Related Art
With reference to FIGS. 1A through 1C, US Patent Public No. 2010/0236544 A1 discloses an outdoor flame heater 100 comprising: a bottom housing 10 being composed of a set of four lower support members 11, a set of four panels 12, and other relative members for installing a gas barrel (not shown); a control box 13 releasing a flame to a gas flame outlet 141 of a base 14 on a top of control box 13; a set of four upper support members 15 together with a plurality of protection guards 16 forming a space for installing a glass tube 17; and a reflector 19 mounted onto a damper 191 and the damper 191 mounted on the upper plate 18 being affixed to the upper support members 15.
Base on the prior features disclosed, a flame F in the glass tube 17 is extended upward by the chimney effect, and the thermal energy radiates from the glass tube 17 while an upper outlet 171 of the glass tube 17 discharges an exhaust gas. Such flame heater 100 not only has a heating function but provides a visual perception of exuberant vitality by looking at the flaming flame. The flame heater 100 also increases the atmosphere and decoration. According to the safety regulations, the overall height of the flame heater 100 is at least 200 cm above to avoid people being in danger of the flame from a top end of the glass tube 17.
Therefore, the kind of flame heater 100 has some drawbacks; for example, the height of the flame heater demanded over 200 cm to comply with the safety regulations but the height h1 of the flame F is only ½˜⅔ height of the glass tube 17; such that there is no flame at an upper region h2 of the glass tube 17. With the reference to FIG. 1C, the heat f from the flame F is discharged through the upper outlet 171 of the glass tube 17, resulting in low temperature at the upper region h2 of the glass tube 17 and affecting the heating effect. Therefore, there is room for improvement.